McKenzie has been in the COO role since 2013, responsible for the telco’s field services, IT and network architecture and operations.

Group executive global enterprise and services, Brendon Riley, will be the interim COO until a replacement is found, while Telstra Group managing director for network applications and services, David Burns, will take on Riley’s role.

“The time is right for me to change direction in my career,” McKenzie said.

“It’s been a wonderful 12 years with Telstra and I am very proud of all the people I have worked with and what we achieved together.”

Telstra CEO, Andrew Penn, said McKenzie had been a positive force for Telstra, supporting four CEOs, and has been a role model for women in the organisation.

McKenzie joined the telco in 2004 as head of Telstra’s regulatory group and was promoted to deputy group managing director for public policy and communications.

McKenzie later progressed to group managing director of strategic marketing and group managing director for Telstra Wholesale.

Prior to joining Telstra, she was the director general of the NSW Department of Commerce and is a former director of Sydney Water and NSW Rail Corporation.

McKenzie's departure comes on the back of telco's recent spate of network outages. During the telco's review in May, McKenzie said it identified three key outcomes and will implement the $50 million worth of recommendations that included increasing redundancy in the nodes, adding more capacity to the core network, introduce new processes and procedures for key network element restarts and improve resilience in its international connectivity.

Copyright 2018 IDG Communications. ABN 14 001 592 650. All rights reserved. Reproduction in whole or in part in any form or medium without express written permission of IDG Communications is prohibited.